Answer:  [-7,-1] 
Explanation: 
range of a function is  that limit in which variation of any function is possible.
general range of sinx is between [-1,1]
-1 sinx
sinx 1                             (A)
1                             (A)
our required function is y= -3sinx - 4
 So, as to obtain this function we will multiply  the each side in Equation (A) by -3 we will get 
-3 -3sinx
-3sinx 3                            (B)
3                            (B)
now subtract from  4 from each side of (B) we will get 
-7 -3sinx-4
-3sinx-4 -1
-1
Hence, required range of the given function y= -3sinx-4 is [-7,-1].